Three little girls got lost in the Florida woods Monday night, and their quick thinking helped law enforcement find them.

Two sisters, Grace Shaffer, 6, and Aubrey Shaffer, 9, and their 13-year-old neighbor wandered into a densely wooded area about two miles from their homes in Lakeland, Fla., early Monday evening hoping to see horses.

"They have boundaries set in the front yard," Missi Shaffer, Grace and Aubrey's mother, told ABCNews.com. "They usually stay within those boundaries. We've never had a problem with them wandering off."

The three girls had passed through a barbed-wire fence into a prohibited area on the way to a nearby horse trail.

"As night began to fall, they got disoriented," Donna Wood, Polk County Sheriff's Office public information officer, told ABCNews.com. "They were pretty far into the area and got lost."

Shaffer was alarmed when she did not see her daughters within their designated play area and checked with her neighbors before calling 911 to report them missing. "We were told a suspicious vehicle had come in near their boundaries," Shaffer said. "Our first thought was they were kidnapped."

After the 13-year-old called her father from her cell phone and told them where they were, the sheriff's office directed their search to the woods, bringing in a helicopter and K-9 authorities.

Soon, however, the 13-year-old girl's cell phone was dying, and Shaffer said her daughters felt cold in the dark woods.

"My oldest one did mention she thought, 'I don't care if I'm grounded forever. I just want to go home,'" Shaffer said.

Lucky for the girls, Aubrey took out her cell phone that she had only ever used for games and music to call 911, "She dialed 911, got Polk emergency call takers, and said, 'Do you know about the lost girls?'" Wood said.

The girls stayed on the phone with Sgt. Emmett Andrews, who asked them to make noise to get the attention of the helicopter and search dogs. "One of the children had shoes that light up," Wood said. "She was banging them together to try to show the light, and they would try to use the cell phone light."

With the help of an infrared system and the efforts of Polk County 911 dispatchers, police patrol, K-9 units, and aviation units, authorities located the girls who went for a helicopter ride back to their parents over two hours after the search began.

"It was a huge relief," Shaffer said. "I was ready for them to run to my arms."

Shaffer said there wasn't any punishment waiting for the girls, "I knew they had learned their lesson."

"These were children definitely wandering looking for an adventure," Wood said. "And they got one."